Hannah has $1000 in her savings account. During 1 month, she withdraws $25. Each successive month, she withdraws $10 more than the previous month. How much remains in her savings account after 10 months?

First month she withdrew $25, second month 35, third month 45, fourth month 55, fifth month 65, sixth month 75, seventh month 85, eight month 95, ninth month 105, tenth month 115

The total she withdrawn after ten months was $700.00. So $1000 - $700 = $300. That is how much that is left after ten months